<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title>利用类选择器画三个盒子</title>
	</head>
	<style type="text/css">
		.box {
			width: 100px;
			height: 100px;
			font-size: 30px;
		}

		.aqua {

			background-color: aqua;
		}

		.greenyellow {
			background-color: greenyellow;
		}
	</style>
	<body>
		<div align="center">
			<div class="aqua box">蓝色</div>
			<div class="greenyellow box">黄色</div>
			<div class="aqua box">蓝色</div>
		</div>

	</body>
</html>
